• 한국분말재료학회지
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• 제20권6호
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• pp.467-473
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• 2013

This research presents a preparation method of dental components by metal injection molding process (MIM process) using titanium scrap. About $20{\mu}m$ sized spherical titanium powders for MIM process were successfully prepared by a novel dehydrogenation and spheroidization method using in-situ radio frequency thermal plasma treatment. The effects of MIM process parameters on the mechanical and biological properties of dental components were investigated and the optimum condition was obtained. After sintering at $1250^{\circ}C$ for 1 hour in vacuum, the hardness and the tensile strength of MIMed titanium components were 289 Hv and 584 MPa, respectively. Prepared titanium dental components were not cytotoxic and they showed a good cell proliferation property.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권6호
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• pp.483-488
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• 1999

The optimal mixing condition of four components gas(Ne,Xe,He,Ar) in PDPs was caculated by a numerical simulation method. The dominated reactions in which $Xe^*(^3P_1)$ is produced and decays were investigated in three components gas (Ne,Xe,He) and our new components gas (Ne,Xe,He,Ar). A peak point of $Xe^*$ density appears in the range of 0.1% to 2% of Ar mixture ratio. The results of simulation show that the direct exitation of Xe by electrons has the greatest influence on the inceasing $Xe^*$ density in both gas mixtures.

• 열처리공학회지
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• 제25권2호
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• pp.80-84
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• 2012

An apparatus was constructed to nitrify small metallic sintered components by using a hollow-cathode discharge plasma method. A stainless steel basket, which contains a sintered part to be nitrified, is potentially grounded and serves as hollow-cathode electrode. Hollow-cathode plasma was produced by supplying the positive voltage to the anode. In this study sintered carbon iron and stainless steel were used as testing specimens. It was shown that an effective nitrifying took place by controlling the total pressure of nitrogen and hydrogen gas and applied voltage.

• 환경생물
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• 제36권2호
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• pp.124-130
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• 2018

본 연구는 넙치 치어(평균 체장 $13.3{\pm}1.6cm$, 평균 체중 $25.6{\pm}3.7g$)를 수중 6가크롬에 10일간 0, 0.5,1.0, $2.0mg\;L^{-1}$의 농도로 노출시켜 독성영향 판단하기 위해 수행되었다. 넙치 hemoglobin과 hematocrit와 같은 혈액학적 성상은 수중 크롬노출에 의해 유의적으로 감소하였다. 혈장 무기성분인 calcium과 magnesium은 크롬노출에 의해 유의적인 변화는 나타나지 않았다. 혈장 무기성분인 glucose와 cholesterol과 같은 $1.0mg\;L^{-1}$ 이상의 크롬노출에 의해 유의적으로 증가하였지만, total protein은 유의적인 변화는 나타나지 않았다. 혈장 효소성분인 AST, ALT, ALP는 크롬노출에 의해 유의적인 증가가 나타났다. 본 실험의 결과는 수중 크롬노출은 넙치의 혈액 및 혈장성분에 유의적인 변화를 유발하며, 이러한 지표의 변화는 수중 크롬노출의 독성영향을 판단하는 주요한 지표가 될 것이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.47-47
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• 2010

Discharge under the water is very hard and demand considerable high voltage. But specially improved electrode can generate plasma discharge to salty water with relatively low voltage. A round shape ceramic electrode having many pinholes combined with metallic one can generate plasma. 400 volt, 10 kHz and 3 micro second pulse width were applied to repeatedly running synthetic seawater with 10 L/m velocity, containing cultivated E. coli and Bacillus. As a result, 18, 94, 99.97, 100, 100 % disinfection rates to E. coli and 17.1, 17.1, 82.9, 99.4, 99.9 % disinfection rates to Bacillus subtilis were achieved to 1, 2, 3, 4, 5 times repetitive treatment respectively. In the plasma condition, the ions and electrons are separated and new kinds of components are re-synthesized by the intensive movement of the components. Especially chlorine ions are separated and recombined to residual free chlorine like HOCl, $OCl^-$. The residual free chlorine concentrations of discharged water were 0.25, 0.88, 1.39, 1.59, 1.66 mg $Cl_2$/L after 5 times treatment respectively. Another unconfirmed radical and oxidants for example, OH, $H_2O_2$, and $O_3$ can have an effect on microorganism of course.

• 한국광학회:학술대회논문집
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• 한국광학회 1991년도 제6회 파동 및 레이저 학술발표회 Prodeedings of 6th Conference on Waves and Lasers
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• pp.64-64
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• 1991

The interaction of high-intensity, focused, nanosecond laser light with matter results in the production of high-temperature plasma, which in turn emits an intense pulse of x rays. The x-ray spectrum consists of strong line components of several keV photon energy and broad continuum. Such an x-ray source provides many advantages over conventional ones for many applications. Pulse nature of the x-ray emission is well-suited for studying transient phenomena and for imaging living biological specimen. Recent experiments have also shown that the laser plasma x ray may be used for x ray lithography. These studies and other applications will be discussed in detail.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1760-1762
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• 2002

In this work we develop an equivalent circuit model of TCP(transformer coupled plasma) source and investigate matching characteristic. The developed circuit model includes transmission line, standard-type impedance matching network and displacement current in the plasma source. The impedance of TCP is calculated by previously developed program for various source parameters and dependance of components of matching impedance on the value of source impedance is investigated.

• 천문학논총
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• 제17권1호
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• pp.7-10
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• 2002

In the earlier papers we analyzed the axisymmetric, nonstationary electrodynamics of the central black hole and a surrounding thin accretion disk in an active galactic nucleus. Based on those papers we analyze the axisymmetric, nonstationary force-free black hole magnetosphere and the motion of the plasma. We concentrate on deriving the relations between the velocity components of the plasma and those of the accreting magnetic field lines. We conclude that the former are given by the sum of the latter and the magnetic field terms.

• 반도체디스플레이기술학회지
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• 제2권4호
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• pp.13-17
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• 2003

An adaptor is designed for chamber impedance measurement of plasma process. Copper rod, fixed board and compensation circuit are the major components of the adaptor. An adaptor can be to measure chamber impedance on time unless stopping a process and Data to measure can do the database. We can use it to a criteria data for a failure diagnosis. So developed adaptor could be used for diagnosis the plasma process chamber in semiconductor industry.

• 전기학회논문지
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• 제58권12호
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• pp.2474-2479
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• 2009

This paper presents an atmospheric microplasma-jet device for bio~medical application. The microplasma-jet device consists of four components; a thin Ni anode, porous alumina insulator, a stainless steel cathode and an aluminum case. The anode has 8 holes, and hole diameter and depth are $200 {\mu}m$ and $60 {\mu}m$, respectively. The discharge test was performed in atmospheric pressure using nitrogen gas and AC voltage at the optimum gas flow rate of 4 Vmin. The plasma-jet is ejected stably for the input voltage ranging from 5.5 to $9.5 kV_{p-p}$. The plasma becomes dense as the input voltage increases, which was verified by the hydrophilicity change of PMMA surface treated by the plasma. The temperature increasement of the aluminum film exposed to plasma-jet illustrates that the micro plasma-jet device is feasible for bio-medical application.